Modular electrical connector



May 14, 1963 D. L.. PHILLIPS ETAL MODULAR ELECTRICAL CONNECTOR 4 Sheets-Sheet 1 Filed June 22, 1959 May 14, 1963 D. L, PHILLIPS ET AL 3,090,027

MODULAR ELECTRICAL CONNECTOR Filed June 22, 1959 4 Sheets-Sheet 2- ll f muunni' jjj face/ w12 IIIIIIIIII;

May 14, 1963 D. l.. PHILLIPS ET AL 3,090,027

MODULAR ELECTRICAL CONNECTOR Filed June 22, 1959 4 Sheets-Sheet 3 f )'15 f6 May 14, 1963 D. L. PHILLIPS ET AL 3,090,027

MODULAR ELECTRICAL CONNECTOR Filed June 22. 1959 4 Sheets-Sheet 4 t @fila/Weiz.; i

United StatesPatent 3,090,027 Patented May 14, 1 963 3,090,027 MODULAR ELECTRICAL CONNECTOR Delbert L. Phillips, 975 Somera Road, Los Angeles 24, Calif., and Joseph S. Jonkey, 1636 W. Mountain Ave., Glendale, Calif.

Filed June 22, 1959, Ser. No. 822,009 6 Claims. (Cl. 339-31) This invention relates to electrical connectors and more particularly pertains to electrical connector units which may be assembled to form multiple conductor connector fittings.

Multiple conductor connector fittings of the prevailing types are unduly expensive because they are of inherently costly construction and for the further reason that mass production is not warranted by the small demand for a connector designed for any specific large number of conductors. A further factor is that the demand shifts continuously under present conditions of rapid technical development. For example, a missile may be designed with a cable or umbilical cord for 4l electrical connections but after two missiles are produced, the number may be raised to 52 connections or lowered to 33 connections.

'It is also a problem to replace a multiple conductor connector fitting without prolonged delay, `It may even be necessary to wait for one to be manufactured and such delay may keep an expensive and essential piece of equipment out of service.

The present invention improves on this situation by providing for a modular construction whereby an electrical fitting for any desired number of conductors may be fabricated from single-conductor modular units. With the single-conductor modular units designed for mass production and so constructed as to permit quick assembly, the resulting multiple conductor connector fittings are of relatively low cost, and especially so since the invention eliminates the necessity of stocking a large number of different sizes of fittings.

An important feature of the invention is that the procedure of assembling a multiple conductor connector fitting from the single-conductor modular units requires no special skill and no special tools or jigs. This feature makes it possible for anyone of ordinary skill to fabricate a special multiple conductor fitting. If a conventional multiple conductor fitting must be replaced in the field, a replacement fitting of modular construction may be fabricated on the spot Without delay.

The invention meets certain problems that arise in carrying out` this basic concept. One problem is to provide single-conductor modular connector uni-ts v that may be readily formed into a bundle of any desired number of units with the bundle unified for functioning -in the same manner as a conventional fitting. Since one bundle may be used fora plug fitting and another bundle used for a cooperating socket fitting, it should be a simple matter to fabricate two identical bundles or any number of identical bundles.

vIt is also a problem to group a number of single-conductor modular units together without permitting either longitudinal or lateral relative displacement among the units. Another problem is to provide-single-conductor modular connector units that may be assembled to form a polarized multiple conductor connector, Le., a multiple conductor connector fitting that will mate with a second multiple conductor fitting at only one orientation of the two fittings relative to each other. A still further problem i-s to provide simple but efficient means for holding the individual single conductor modular units together in a bundle.

The invention meets these problems by providing singleconductor modular connector units in 'the form of smal-l elongated bodies of non-conducting material adapted to house either plug connector members or socket connector members. A feature of the invention -is that the plug and socket connector members may be supplied separately for assembly to the non-conducting bodies, each modular body being adapted to receive and retain either a plug member or a socket member.

The non-conducting bodies are shaped to interlock in a manner to prevent relative displacement of the assembled bodies in a bundle. For this purpose, each of the multiple sides of a modular body has a pattern of projections and recesses with the patterns of different sides complementary to each other for effective interlocking of the contiguous bodies in a bundle.

In the preferred practice of the invention, these patterns of projections and recesses are so designed that any selected modular body in a bundle may be interlocked with the adjacent bodies at a position shifted longitudinally from the adjacent bodies. Thus with one single-conductor modular body of a multiple conductor plug fitting either advanced or retracted, and with the corresponding modular body of the complementary multiple conductor socket titting correspondingly advanced or retracted, the two fittings may be connected together Iin only one orientation of the two fittings relative to each other.

In some instances, where accurate assembly is essential for fittings that are to be interchangeably connected, it iis desirable that the modular bodies interlock in a manner to prevent relative lateral displacement as well as relative longitudinal displacement of the bodies. For this purpose, some practices of the invention provide patterns of projections and recesses for the sides of the modular bodies that permit abutting bodies to interlock at accurately predetermined relative positions in a positive manner for the prevention of relative lateral displacement. In other practices, the same purpose is achieved by shaping the modular bodies in cross section to fit or wedge together accurately at predetermined relative positions.

The various features and advantages of the invention may be understood from the following detailed description together with the accompanying drawings.

In the drawings, which are to be regarded as merely illustrative: Y

FIG. 1 is a longitudinal ysectional view showing how a single-conductor modular unit incorporating a plug connector member mates with an identical modular unit incorporating a socket connector member;

FIG. 2 is a side elevation of one of the modular bodies;

FIG. 3 is a transverse section taken as indicated by the line 3-3 of FIG. 2;

FIG. 4 is an end elevation of an assembly or bundle of single-conductor modular bodies showing the manner in which the contiguous bodies fit together;

FIG. 5 is a fragmentary longitudinal section taken as indicated by the line 5-5 of FIG. 4 and showing how a pair of contiguous single-conductor modular bodies interlock to prevent longitudinal displacement relative to each other;

FIGS. 6 and 7 are fragmentary transverse sections taken as indicated by the lines 6 6 and 7-7 respectively of FIG. 5 and showing how a pair of contiguous modular bodies interlock to prevent lateral displacement relative to each other;

FIG. 8 is a side elevation of two complementary multiple conductor connector fittings ythat are polar-ized to fit together at only one relative orientation;

FIG. 9 is a section taken as indicated by the line 9 9 of FIG. 8 showing how the multiple conductor plug fittingV of FIG. 8 has a longitudinally advanced modular body;

FIG. 10 is a cross section along the line 10-10 of FIG. 8 showing how thek multiple conductor socket fitting of F-IG. 8 has a corresponding modular body correspondingly retracted longitudinally;

FIG. 11 is a diagrammatic view showing how a pair of cooperating multiple conductor fittings may be polarized by using at least one blank modular body in the multiple conductor socket fitting;

FIG. l2 is a diagrammatic view indicating how a pair of multiple conductor fittings may be polarized by using both plug connector elements and socket connector elements in each of the two bundles of modular units;

FIG. yl5 is a side elevation showing how a pair of multiple conductor fittings embodying the principles of the invention may be employed to connect two multiple conductor cables;

FIG. 14 is a fragmentary view, partly in side elevation and partly in section, showing how a cable may be connected to the housing of an electrical apparatus in a stress-free manner;

FIG. 15 is a side elevation of a single-conductor modular body that is of triangular cross-sectional configuration;

FIG. 16 is a cross section along the line :I6-16 of FIG. l5 showing the triangular configuration;

FIG. 17 is an end elevation of an assembly of modular units of the configuration shown in FIGS. l5 and 16;

FIG. 18 is a side elevation of a modular body of generally hexagonal cross-sectional configuration;

FIG. 19 is a transverse section of the modular body taken as indicated by the line 19-19 of FIG. 18;

FIG. 20 is an end elevation of an assembly of modular bodies of the configuration shown in FIGS. 18 and 19; and

FIGS. 21 to 24 are diagrams of patterns of projections and recesses for the sides of modular bodies that may be employed in different practices of the invention.

In the first form of the invention illustrated in FIGS. 1 to 7, each of the modular bodies, which is generally designated by numeral 30, is of generally rectangular` cross-sectional configuration or, more specifically, is of generally square cross-sectional configuration. It is contemplated that the modular bodies 30 will be made of suitable plastic material and, for high temperature installations, will be capable of withstanding relatively high temperatures. For high temperature installations, the modular bodies may be made of such materials as Kel-F, Teflon or irradiated polyethylene.

Each of the four sides of a modular body 30 has a pattern of projections and recesses with the patterns of different sides complementary to each other so that the bodies may be grouped together in a bundle to form a connector fitting with the contiguous bodies in a bundle in interlocking engagement with each other. As shown in FIG. 2, each of the four longitudinal sides of a modular body 30 may have a pattern consisting of four projections 32 and four recesses 34, the projections and recesses alternating in staggered relationship. The projections 32 are fiat plateaus and the recesses 34 are correspondingly shaped and dimensioned flat-bottomed recesses.

It is apparent that if the four sides of a modular body 30 has the described pattern of projections 32 and recesses 34, the abutting sides of a pair of the modular bodies will have patterns that are complementary to each other in the sense that the four projections 32 of one body `will seat in the four recesses 34 of the adjacent body for effective interlocking of the two bodies.

The manner in which such a pair of bodies interlock may be understood by reference to the sectional views, FIGS. 5, 6 and 7. FIG. 5, which is a longitudinal section shows how the two modular bodies interlock with two opposed pairs of transverse shoulders to prevent relative movement of the two bodies in either longitudinal direction. Thus in FIG. 5, the projection 32 of one of the two modular bodies 30 forms a transverse shoulder 35 which is paired with and abuts a transverse shoulder 36 formed by a projection 32 of the other modular body. to prevent relative movement of the two bodies in one longitudinal direction and the same projection 32 provides a second transverse shoulder 38 which abuts a second 4 transverse shoulder 40` of a second projection 32 of the other modular body to prevent relative shift of the two bodies in the opposite longitudinal direction.

FIG. 6 shows how a projection 32 of one of the two modular bodies 30 forms a longitudinal shoulder 42 in abutment against a similar longitudinal shoulder 44 of a projection 32 of the other modular body to prevent shift of the two bodies relative to each other in one lateral direction; and FIG. 7 shows how a second longitudinal shoulder 45 formed by a second projection 32 of the one modular body abuts a longitudinal shoulder 46 of a projection 32 of the second modular body to prevent relative shift between the two bodies in the opposite lateral direction. Thus this pattern of projections and recesses permits two contiguous modular bodies 30 to be interlocked in a positive manner against both lateral and longitudinal displacement relative to each other. It is apparent that any number of the modular bodies 30 may be grouped together with the whole assembly interlocked to function in the same manner as a single integral body. ,l FIG. 4 shows such a bundle of interlocked modular bodies 30. The modular bodies 30 of the bundle may be held together, for example, by wrapping a strand of glass fibers 48 around the bundle and bonding the strand by a suitable heat-resistant adhesive. It is apparent that any desired number of the modular bodies 30 may be grouped and secured together in this manner.

Within the scope of the invention, electrical plug connectors and electrical socket connectors may be mounted in modular bodies 30 in any suitable manner. A feature of the preferred embodiment of the invention, however, is the concept of plug connector members and socket connector members that may be mounted in the modular bodies 30 by the simple step of forcing the connector members into longitudinal passages of the modular bodies. The connector members may be first crimped to engage corresponding wires and then the connector members may be pushed into the modular bodies of an assembled group of modular bodies.

As shown in FIG. l, a modular body 30 may be formed with a longitudinal or axial passage 50 therethrough. The passage 50 is reduced in diameter at an intermediate point to form a rearwardly facing annular shoulder 52. Preferably the for-ward end of the passage 50 is formed with a radially inward lip or flange 54.

FIG. 1 shows a plug connector member, generally designated 55, that is adapted for connection to a wire 56 and is further adapted to be mounted in the passage 50 of a modular body 30. The plug member 55 consists of a pin or prong 58 of conducting material such as copper mounted in a conducting sleeve 60. The pin may be secured in the sleeve in any suitable manner, for example by staking, crimping or furnace-brazing. The conducting sleeve 60 may be attached to the wire 56 by crimping the sleeve as indicated at 62.

The conducting sleeve 60 is formed with a circumferential shoulder 64 to abut the passage shoulder 52 and thereby lock the plug member 55 against forward longitudinal shift relative to the modular body 30. The rear end of the conducting sleeve 60 may ybe flared as shown at 65 to make the rear circumferential edge of the con ducting sleeve Islightly oversized with respect to the surrounding passage 50. Since the modular body 30 is made of resilient plastic material, the passage 50 readily expands to admit the fiared end 65. The flared end 65 of the sleeve is readily movable forward in the passage but digs into the surrounding plastic material to resist rearward retraction in a positive manner. Thus, the plug member 55 may be permanently `installed in a plastic modular body 30 simply :by manually forcing the plug member into the passage 50 of the modular body after the plug connector has been crimped onto the end of the wire 56. It will be noted that the pin 58 of the installed plug member 55 extends forward from the forward end of the modular body to dt into a complementary socket con- Inector member.

FIG. 1 also shows bow a socket connector member, generally designated `66, m-ay be mounted in a modular body 30 in the same general manner. In the particular construction shown, the socket connector member 66 comprises a conducting sleeve 68 in wh-ich are mounted the base ends of a cluster of wires 70 which are `of hel-ical configuration to form a socket to receive the pin 58 of the plug member 55. rPhe base ends of the wires 70 are secured in the conducting sleeve 68 by crimping, as indicated at 72. The conducting sleeve 68 is also adapted to engage the end of a circuit wire 74 by crimping as indicated at 75. The forward end of the conducting sleeve 68 forms a circumferential shoulder 76 to abut the passage shoulder 52 of the modular body and the re-ar end of the conducting sleeve may be formed with a flare 78 for the previously described purpose.

FIGS. 8 to 12. illustrate various ways in which a multiple conductor connector fitting comprising a bundle of the described connector units may be polarized so that two cooperating multiple conductor connector fittings of the described construction m-ay be iitted together at only one orientation of the -two yfittings relative to eac-h other.

FIGS. 8 to 10 show bow this purpose may be accom plished simply by longitudinally displacing one of the modular bodies in each of two complementary multipleconductor connector iittings. FIGS. 8 and 9 show a fou-rconductor plug fitting generally designated 80 in which one modular body 30m is displaced forward yfrom the other modular bodies of the bundle. It is apparent that the previously described pattern of projections 32 and recesses i34 on each of the four sides of a modular body 30 permit two of the modular bodies to interlock effectively at relative positions 'at which one-half of one modular body extends longitudinally beyond the other modular body.

The complementary four-conductor socket fitting, generally designated 82 in FIGS. 8 and 10, bas a modular body 60h displaced longitudinally rearward, the modular body 30b corresponding in posi-tion to the modul-ar body 30a. It is apparent that the pair of four-conductor connector fittings y80 and 82 may be fit-ted together only at the one orienta-tion where the Iforwardly projected modular body 30a may enter the recess formed by fthe retraction of the modular body 3012.

FIG. 11 shows another method of fabricating -a pair of cooperating multiple-conductor fittings for polarization. The three-conductor iitting generally designated 84 includes three modular bodies 30 equipped with plug members 55. Ihe three modular bodies 50 are grouped with a fourth blank modular body 30C, the modular body 30C being a solid body with no passage 50 therein. The three-conductor socket tting y85 for use with the plug litting 8d has three modular bodies 30 equipped with socket members 66 together with a fourth blank modular body I30C. The two blank bodies 30e are at corresponding positions in the two lfittings. It is apparent that there is only one of the fou-r possible relative orientations of the two fittings at which the three plug members 55 of the fitting `84 will enter the three socket members 66 of the fitting 85.

FIG. i12 shows a `four-conductor connector tting, generally designated S6, yfor use with a second four-conductor connector fitting, generally designated 88, at -a predetermined relative orientation of the two fittings. The connector fitting 38 comprises three modular bodies G0 equipped with three plug connector members S5 grouped with a fourth modular lbody 30 equipped with a socket connector member `66.V The second `fitting 88 comprises three modular bodies 30 equipped with three socket members `66 in positions corresponding to the three plug members and a `fourth modular body 30 equipped with a plug member 55 at the position corresponding to the socket member 66 of the itting 86. There is only one of the four possible orientations fof lthe connector fitting 86 rela- 6 tive to the connector fitting 8'8 at which the three plug members 55 will enter lche three socket members 66 with the single socket member 66 of the fitting 86 receiving the single plug member 55 of the fitting 88.

FIG. 13 shows how two multiple conductor cables 90 and '92 may be interconnected by a pair of modular connector fittings of the character described. The individual conductors or wires of the cable are connected to cor-responding connector members in a first bundle of modular bodies 30 land in like manner the individual conductors cr wires of the second cable 92 are connected to complementary connector members that are mounted in a second bundle of modular bodies 30. A sleeve 94 of irradiated polyethylene plastic is then slipped over one of the two bundles of modular bodies and after the two bundles are fitted together for electrical interconnection of the two cables, the sleeve is centered to cover both bundles. Heat is then applied to the irradiated plastic sleeve .to cause the sleeve to shrink in circumference for snugly fitting the interengaged bundles and the adj-acent portions of the Itwo cables 90 and 92.

FIG. 14 illustrates the manner in which a repair in the field may be made which involves the replacement of a conventional connector fitting on a piece of apparatus. 'Ihe apparatus has a housing A95, one wall of which has an opening 96 which is provided with some type of conventional multiple-conductor fitting. -Usually such a litting is mounted in the opening 96 by some type of grommet structure.

To make the repair, the defective tting and the associated grommet structure are removed and a special sleeve 97 of ru'bberdike material having 'a fabric liner 98 is substituted. Preferably the sleeve 97 is of elongated tapered configuration as shown and is formed with a circumferential groove at its base end by means of which it may be mounted in the housing opening 96 in the manner shown. A special `grommet 99 of rigid material may be inserted in the base end of the sleeve 97 aiter the sleeve is mounted in the opening 96. The grommet 99 has a circumferential bead 100 on its inner end that spreads the material of the sleeve against the rim of the opening `96 and thereby greatly increases the resistance of the sleeve to withdrawal from the opening.

'I'he original conductors from the original connector fitting to the components inside the housin-g 95 are replaced by a new set of wires 102 which extend through the sleeve 97. The plurality of wires 102 are connected to corresponding connector members in a bundle of modular bodies and the wires 104 of a cable that is to be connected to the apparatus are connected to corresponding connector members in a second bundle of modul-ar bodies. The two bundles of modular bodies are fitted together and are then encased in a plastic sleeve 94 in the same manner as the previously described structure shown in FIG. 13.

FIGS. 15 to 17 show how modular bodies 105 of triangular cross-sectional configuration may be employed in the same manner as the first described modular bodies 3 0 of rectangular cross-sectional configuration. Each of the three faces of a modular body 105 shown in FIGS. 15 `and 16 has a suitable pattern of projections and recesses for interlocking engagement of the contiguous bodies in a bundle. This pattern may be like the previously described pattern consisting of projections 106 like the previously mentioned projections 32 and recesses 108 like the previously described recesses 34,. Thus the contiguous triangular modular bodies will interlock against both longitudinal and lateral displacement relative to each other in the same manner as the previously described modular bodies 30.

FIG. 17 shows how any number of the triangular modular bodies 105 may be -grouped in -a bundle to form a multiple-conductor connector fitting. A bundle 'may consist of only two modular bodies 105e and 105b. A bundle of three may comprise modular bodie-s 105a, 105b and 105e. Body '105d may be added to make a bundle of four. A compact bundle of six may comprise bodies 10511, 105e, 105:1, 165e, 105] and 105g. In each of these bundles, the modular bodies may be held securely together by any suitable encircling means such as a strand of glass fibers bonded by adhesive, as heretofore described.

FIGS. 18 to 20 show how modular bodies 110` of generally hexagonal cross-sectional configuration may be employed in the same manner as the previously described rectangular and triangular bodies. As shown in FIGS. 18 and 19, a modular body 110 may have a configuration which consists. of successive longitudinal sections integral with each other, each of which sections has three relatively narrow sides and three alternate wider sides, the successive sections being rotated 60 from each other. As shown in FIG. 18, there are four such longitudinal sections angularly offset from each other. This conguration provides six longitudinal rows of projections and recesses on the vsix sides of the body, respectively, each row consisting of two relatively narrow projections 112 and two alternate relatively wide recesses 114.

It is apparent that this configuration makes it possible for the contiguous modular bodies 110 in a bundle to interlock against relative longitudinal movement. FIG. 20 illustrates the -fact that any number of the modular bodies 110 may be bundled together to form a multipleconductor fitting.

The underlying principles involved in the interlocking engagement of modular bodies in a bundle may be under stood by referring to the diagrams in FIGS. 21 to 24. Each of these figures shows the successive longitudinal sides of modular bodies of polygonal cross-sectional configuration, the shaded areas indicating projections and the blank areas indicating recesses.

For effective interlocking of the modular bodies in a bundle in a manner to prevent relative longitudinal displacement of the individual bodies, what may be termed a minimum pattern shown in FIG. 2l may be employed. It is apparent that the patterns of each pair of successive sides are complementary to each other in the sense that each pair of successive sides would interlock if one of the pair were folded over against the other. FIG. 21 represents the four sides of a modular body of square cross-sectional configuration.

It is apparent that while the patterns shown in FIG. 21 will lock contiguous bodies against relative longitudinal displacement, they will not lock contiguous bodies against relative lateral displacement. In many instances, modular bodies of rectangular cross-sectional configuration may be grouped together. with suicient accuracy without providing for interlocking engagement against relative lateral movement.

If polarized fittings of the previously described character shown in FIG. 8 are not required, the minimum pattern in FIG. 21 may be used in which each side is in effect divided into three panels. For the polarized fittings of FIG. 8, the pattern shown in FIG. 23 may be used in which each side is divided into four panels.

The patterns for sides of modular bodies shown in FIGS. 21 and 23 may be used for any modular body of polygonal cross-sectional configuration that has an even number of sides. Thus these patterns may be employed for modular bodies of square cross-section and modular bodies of hexagonal cross section. They are not satisfactory for modular bodies of triangular cross section if many modular bodies are to be used in one bundle.

The interlocking of the contiguous bodies in a bundle against relative lateral displacement is desirable for unifying the bundle but in many instances is desirable for the more important reason of accurately positioning the bodies relative to each other so that two bundles, each comprising a relatively large number of modular bodies, will be identical in cross section to fit together without trouble. If the modular bodies are so shaped as to wedge or mesh together, however, interlocking of the projections and recesses of contiguous bodies against relative lateral displacement of the bodies to achieve accurate relative lateral positioning of the bodies becomes unnecessary. The cross-sectional configuration that permits the bodies to mesh or wedge together inherently serves the same purpose. For example, it can be seen that the triangular bodies in FIG. l5 and the hexagonalbodies 110 in FIG. 20` inherently fit together in predetermined relationships so that it is not at all difiicult to fabricate two identical bundles. Modular bodies of square cross-sectional configuration, however, do not mesh together in this manner and therefore interlocking engagement against relative lateral displacement is desirable for modular bodies of square cross section when a large number of such bodies are bundled together to make a multiple-com ductor connector.

FIG. 22 is a minimum pattern of projections and recesses to provide interlocking against both lateral and longitudinal relative displacement. This pattern, unlike the pattern of FIG. 2l, may be used for a triangular modular body since the sides of each pair of successive sides are complementary to each other. If interlocking engagement against lateral displacement as well as longitudinal displacement is required and, additionally, it is required that the modular bodies be adapted for fabricating polarized fittings in the manner illustrated by FIGS. 8 to l0, the pattern shown in FIG. 24 may be employed. This is the pattern employed for the previously described rectangular modular lbodies 3i) and the previously described triangular modular bodies 105.

Our description in specific detail of the selected practices of the invention will suggest various changes, substitutions and other departures from our disclosure within the spirit and scope of the appended claims.

We claim:

l. A modular electrical connector unit for grouping in a bundle with identical units in side by side relationship to make a multiple conductor connector fitting, said unit comprising: a conductor member to mate with a complementary conductor member; and an insulating body surrounding and holding said conductor member, the length of said body being divided into at least four sections of equal length, each of the sections being of uniform crosssectional configuration throughout its length, all of the sections having the same number of peripheral faces and all of the sections being of `the same general cross-sectional configuration, the alternate sections Abeing identical and the successive adjacent sections being offset relative to each other to form Ilateral projections and recesses to interlock the contiguous bodies against relative longitudinal movement, all of said sections being of equal length.

2. A modular electrical connector unit as set forth in claim 1 in which each of the sections of the two sets is generally polygonal in cross-sectional configuration and each ofthe sides of each of the sections is divided lengthwise into two portions, the surfaces of which are in two spaced parallel planes with a longitudinal shoulder at the juncture of the two portions.

3. A modular electrical connector unit as set forth in claim l -in which all of Ithe sections of the two sets are of identical polygonal cross-sectional configuration with the cross-sectional configurations of the two alternate sets rotated relative to each other to form the projections and recesses.

4. A modular electrical connector unit as set forth in claim 1 in which said body is made of resilient plastic material with a longitudinal passage of uniform cross section therein with a shoulder in the passage; in which said conductor member is mounted in said passage in abutment with said shoulder to prevent displacement of the conductor member relative to the body in one longitudinal direction; and in which said conductor member has a fiared tubular end portion directed oppositely with respect to said shoulder, said flared end being oversized relative to said passage and engaging the surrounding Wall of the passage to prevent longitudinal displacement of the conductor member relative to the body in the opposite longitudinal direction, whereby the conductor member may be installed in the body by merely forcing the conductor member into said passage against said shoulder.

5. A joint structure for connecting a first plurality of conductors with a second plurality of conductors, comprising: a first bundle of insulating bodies and a second bundle of insulating bodies corresponding respectively to said rst and second pluralities of conductors; a rst set of connector members for connection to said tirst plurality of conductors and mounted in the respective insulatingbodies of said first bundle; and a second set of connector members mounted in the respective insulating bodies of said second bundle for connection to said second plurality of conductors and shaped for mating with said iirst set `of connector members, each of the bodies of each of said bundles having multiple sides to abut sides of the adjacent bodies in the bundle, each of said sides having a pattern of projections and recesses with the patterns of diterent sides complementary to each other for interlocking of the abutting bodies yin a bundle, one body of said irst bundle that is spaced laterally from the longitudinal axis of the bundle being -displaced longitudinally forward `and the corresponding body of the second bundle being displaced correspondingly rearward to permit the two sets of connecting members to mate at only one relative orientation of the two bundles.

6. An electrical connector unit comprising: a connector member to mate with a complementary connector member; and a body of resiliently deformable insulating plastic material having a longitudinal passage of circular cross section with a shoulder therein `facing in one longitudinal direction, said connector member being circular in cross section fand dimensioned Ito fit in said passage and having a shoulder to abut said passage shoulder to prevent relative longitudinal displacement of the member in the opposite longitudinal direction, said member having a tubular end portion to receive the end of 4a wire, said tubular end portion being formed with a ared rim facing in said one longitudinal direction to permit the member to be inserted in said passage in the opposite longitudinal direction said ared rim being oversized in ldiameter relative to said passage to expand the passage land dig into Ithe surrounding wall of the -passage to prevent retraction of the inserted member in said one longitudinal direction.

References Cited in the le of this patent UNITED STATES PATENTS 2,171,331 Folsom Aug. 29, 1939 2,384,267 Andersen Sept. 4, 1945 2,469,397 Mezek May 10, 1949 2,557,818 Eddy June 19, 1951 2,701,869 Hobson Feb. 8, 1955 2,712,119 Strubel lune 28, 1955 2,750,572 Fox June l2, 1956 2,782,459 Moncrief Feb. 26, 1957 2,821,155 Seckel lan. 28, 1958 2,828,474 Fox Mar. 25, 1958 FORETGN PATENTS 630,333 Great Britain Get. 11, 1949 

1. A MODULAR ELECTRICAL CONNECTOR UNIT FOR GROUPING IN A BUNDLE WITH IDENTICAL UNITS IN SIDE RELATIONSHIP TO MAKE A MULTIPLE CONDUCTOR CONNECTOR FITTING, SAID UNIT COMPRISING: A CONDUCTOR MEMBER TO MATE WITH A COMPLEMENTARY CONDUCTOR MEMBER; AND AN INSULATING BODY SURROUNDING AND HOLDING SAID CONDUCTOR MEMBER, THE LENGTH OF SAID BODY BEING DIVIDED INTO AT LEAST FOUR SECTIONS OF EQUAL LENGTH, EACH OF THE SECTIONS BEING OF UNIFORM CROSSSECTIONAL CONFIGURATION THROUGHOUT ITS LENGTH, ALL OF THE SECTIONS HAVING THE SAME NUMBER OF PERIPHERAL FACES AND ALL OF THE SECTIONS BEING OF THE SAME GENERAL CROSS-SECTIONAL CONFIGURATION, THE ALTERNATE SECTIONS BEING IDENTICAL AND THE SUCCESSIVE ADJACENT SECTIONS BEING OFFSET RELATIVE TO EACH OTHER TO FORM LATERAL PROJECTIONS AND RECESSES TO INTERLOCK THE CONTIGUOUS BODIES AGAINST RELATIVE LONGITUDINAL MOVEMENT, ALL OF SAID SECTIONS BEING OF EQUAL LENGTH. 